package com.atguigu.juc.java8基础;


import com.sun.jmx.snmp.tasks.ThreadService;

import java.util.concurrent.*;

class MyTask extends RecursiveTask<Integer> {

    private static final Integer ADJUST_VALUE = 10;

    private int begin;
    private int end;
    private int result;

    public MyTask(int begin, int end) {
        this.begin = begin;
        this.end = end;
    }

    @Override
    protected Integer compute() {


        if (end - begin <= ADJUST_VALUE) {
            for (int i = begin; i <= end; i++) {
                result = result + i;
            }
        }else {
            int middle = (end + begin) / 2;
            MyTask task01 = new MyTask(begin,middle);
            MyTask task02 = new MyTask(middle+1,end);
            task01.fork();
            task02.fork();
            result = task01.join() + task02.join();
        }
        return result;
    }

}


public class ForkJoinDemo {

    public static void main(String[] args) throws ExecutionException, InterruptedException {

        MyTask myTask = new MyTask(0,100);

        ForkJoinPool threadPool = new ForkJoinPool();

        ForkJoinTask<Integer> forkJoinTask = threadPool.submit(myTask);

        System.out.println(forkJoinTask.get());

        threadPool.shutdown();


    }

}
